Ottawa - Canadians would support using energy supplies as a bargaining chip if the United States tries to reopen the North American Free Trade Agreement, a new poll suggests. 

Respondents to The Canadian Press Harris-Decima poll generally like NAFTA and were willing to play hardball against the Americans in any renegotiation.

Almost half of them felt that NAFTA has been good, or very good for the economy, while only 27 per cent thought it's a bad deal. 

The survey suggests that 61 per cent of people would support using oil as a lever if Washington demands a renegotiation of the treaty. 

Barack Obama, the Democratic presidential contender, has said he wants to open up the deal, which embraces Canada, the United States and Mexico.

Bruce Anderson, Harris-Decima president, said Canadian support for NAFTA includes majorities of both Liberal and Conservative voters, although NDP support is much weaker.

"Canadians like the idea of free trade," he said. 

They're ready to be tough in negotiations, he added. 

"They would prefer not to reopen the agreement, but would expect their government to take a strong bargaining stance if the agreement were to be reopened because of developments in the United States."

He said they understand that Canadian energy exports are important to the United States and would make a good bargaining chip.

The poll questioned just over 1,000 people in an omnibus telephone survey between Feb. 28 and March 3 and is considered accurate to within 3.1 percentage points 19 times in 20.